Process for bonding teeth to dental plates



May l0, 1949. w. Gil-:SE '2,469,822

v PRocEss' Fon BoNDING TEETH To DENTAL PLATES Filed Aug. 31,` 1946 IN VEN TOR.

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Patented May 10, 1949 PROCESS FOR BONDING TEETH TO DENTAL PLATES Walter Giese, Chicago, Ill.

Application August 31, 1946, Serial No. 694,341

3 Claims.

This invention relates to the replacement or tightening of broken-out or loosened teeth in `a dental plate.

Specicaliy the invention deals with a greatly simpliiied method of replacing broken lout teeth in dental plates, and includes apparatus for carrying out the process.

According to this invention, the dental plate, having a tooth broken out of its mounting in the plate, can be quickly repaired without evidence of patching or other repair work. The invention is operative with the Commonly `used vulcanized rubber dental plates as well with the new plastic material dental plates such as acrylic resin plates.

Heretoiore when a Itooth was broken out of, or loosened from, a dental plate it was necessary -for the dentist to send the `plate to a dental laboratory for undergoing a complicated process, involving complete investment of the plate `in a mold, to replace the broken out tooth. The present invention now so greatly simplifies the replacement of loosened or broken out teeth in dental plates that it is possible for the dentist himself to quickly replace the broken out or loosened tooth and return the repaired plate to the patient within an hour or so. As a result of the invention, it is no longer necessary for plate wearers to carry an extra set of plates, 0r to go without their plates while they are being repaired.

According -tc this invention, a, dental plate with one or more broken out teeth 'is rst cut and scraped to form a recess in the plate behind the tooth space in which the broken out tooth was set. A new tooth, or the broken out old tooth if undamaged, is then set in the tooth space and a dab of dental wax is pressed into the recess and against the hack face of the toot-h for temporarily holding the tooth. in position. Plaster of Paris is then spread `across the front `face of the wax-held tooth and across the front faces of the adjacent teeth to form a dam or bridge. A relatively thin strip of heat-conducting material such as copper, aluminum, or the like is inserted into the plaster covering before the plaster has set. The strip is positioned to lie in closely spaced relation in iront of the wax-held tooth and in Ispaced relation. from the materialof the dental plate.' The plaster of Paris is then allowed to set. The wax is next mel-ted out of the recess and this recess is packed with unset thermosetting material preferably of the same composition as the plate material. The thermosetting material is shaped to ll the recess and is also vide a process of pressed against the back face of the tooth to continue the normal contour of the plate. After the thermosetting material is shaped to the proper contour, it is covered with plaster of Paris and the entire tooth may be invested in plaster of Paris. The metal strip is next heated, preferably by contact with an electrically heated element, and the heated strip will heat the set plaster of Pari-s for setting the thermosetting material into intimate bonded relation with the tooth and the plate. After the setting or curing operation the plaster of Paris is broken off of the plate and tooth, the thermoset material is ground if necessary, and polished, and the repaired plate is ready for immediate use.

A feature of the invention is the speed with which the process can lbe carried out so that lost wearing time of a dental plate is reduced to a minimum.

A further feature `of the invention resides in the use of localized heat to set the bonding material for the tooth so that the plate will not be burned or scorched and thereby discolored.

It is, then, an object of this invention to proquickly repairing dental plates without investing the entire plate in a mold and without subjecting the entire plate to heat.

A further object of the invention isto provide a method of quickly replacing broken out teeth in dental plates with-out discoloring even the most heat-sensitive plate material.

A still `further object of .the 'invention is to provide a -process for vulcanizing a new tooth in position in a dental plate with localized heat supplied to a small plaster mold formed around the tooth being replaced.

A specific object of the invention is to provide a process for replacing teeth in dental plates by investing the new .tooth and the adjoining teeth and plate areas only in a plaster mold, followed by a localized heating of the mold to set thermosetting material of the same composition vas the plate and also invested in the mold.

A -specic object of the invention is to provide lheating' strips vand a heating element for locally heating a plaster cast on a dental plate without scorching the plate.

Other and further objects of the invention will be apparent tothose skilled in the art from `the following detailed description of the annexed sheet of drawings which, hyp-way of a preferred example only, illustrates one embodiment of the invention. Y I

On the drawings:

4Figure 1 is a vfragmentary plan view of a dental plate having a tooth removed and having the area behind the tooth space recessed in accordance with vthis invention.

Figure 2 is a cross-sectional view taken along the line lI-II `of Figure 1 but illustrating a new tooth held in the tooth space 4by means of a dab of wax seated in the recess.

Figure 3 is a plan view similar to Figure 1 but illustrating the :plaster mold formed aroundy-the front faces of the-:tooth being replaced andithe adjacent teeth.

Figure 4 is a cross-sectional View taken along the line IV-IV of Figure 3.

Figure 5 is a view similar to Figure 4-butiliustrating the Wax removed from the recess.

Figure 6 is a view similar to Figure 4 hutfil1us trating the thermosetting material packed in the recess and against the tooth and also showing the manner in which the material iscovered with a mold.

Figure 7 is a vertical cross-seotionalview taken through a heating .unit illustrating the manner inwhic-h the assembl'yof Figure 6 is mounted thereon for. the heating operation.

Figure 8 is. anisometric .vien/.of one .form .of heating I stripv according ,to this. invention: suitableforuse.- in the replacement ofA asingle. tooth on afdental plate.

Figure. Sis aview similar toFigure 8 4butl'illustrating aheating stripsuitableior usen replacing a.Y plurality ot adjacent. .teeth in a dental plate.

l As. shown 0n thedrawings;

Asillustrated. in .Figure I, a dental plate `I'll with the conventional teeth I'I anchored therein, has. a blank toothspacefl'z formed by abi-cken out tooth. Asis. conventionaL'the lingual side of. the gingival' portion I'Darofthe platem is built up between the teeth II and to a level only slightlybelowthe.occlusalsurfaoes of the. teeth.' This lingualsideof .the gingival portion has a good bonding and backing up area yfor thel teeth so that they will bermly. attached tothe plate.

In accordance withthis invention' the llingual sideof thegingiualportion 'Illa is rsty recessed atlllbejhind thetooth space i2." Therecess-is provided by cutting out. some. of the plate materialtwith a .scraping `or grinding. action. The Walls-oi` the recess 'will be .relatively roughto affordgood. anchoring, surfaces.

As shown in Figure a new tooth 'Id is positionedv in the tooth space`.l`2 and',V of course, is sized and selected to match.with` the adjoining teeth andto, fl't the tooth space. If the broken out tooth is. undamaged, itv may be refused. The lingual side of the new tooth I4, as isiconventinnal,v` is equipped with anchoringv pins such as I5.

[Therecess Imis next preferably filled with a dab. of. wax- 116. which is iirmly .pressed into the recess. and against the lingual` side oi the newv tooth t4 to temporarily anchor the tooth in proper positionin the. tooth Space l2.

As shown in Figures 3f and 42,. thefront. facelof thenew tooth [4I-.and theiront faces ofA the.v adjoining, teeth `I I' together with. the buccal'gingival,

portion. IIllioi the .plate 'I0` is invested in plaster of Paris I"I'."`This plaster of Paris extends. locally around .the new toothll. .as shown, and only a smalllamount need .be used. Y Before thepl'aster of .Barisis set, thestripend. 13a oi"v a. heatecon dructngf. iitting "1,8 .isinserted therein. tof. lie in closelyl spaced relationin frantoithe newY tooth best shown in Figure 4. posed of,heat-.conductingmetalvsueh as. aluminum is-next packed with thermosetting bonding ma- ,teriallnasshown in Figure 6, and this thermo- ;;setting..material; ywhich has the consistency of putty, is carefully worked into position in the .creoessnwirmly engage the lingual side of the new tooth I4 and to receive the anchoring pins I5 completelyitherein.Thel'packing of the bonding ma- .f-.teria.lwill not shift the tooth I4, since the plaster mold I9 firmly anchors* the tooth in position. The .thermosettingmaterial 2I'Iv is shaped to .the contouroi the lingualv gingi'val portion,...and..s next covered with 'plaster of Paris 2I to, coact with .the mold I9 and totallyv invest theth-erinosetting material 2U.' After. theplaster ZI has been seti, boththe `new tooth I4., the adjoining .teeth Il, the adjoining 'gingival portions [da and I b ofthe plate I.0, the thermosetting materialZILand the tip end.' [8a ofthe ttingjlare all.completely invested in a rigid mold. The assembly is' then mounted on a heating `.unit 22shown in Figure 1. This unitj22 .has` a post --23 .projectingpupwardly from the top' thereof and', sized` to .receive the collar T817 'of the fitting I8 thereon. "The postl 23 lis heatedto heat the collar' IE6 of the tting I8 from. the strip 'Ilia and progressively sets into. a.

thermoset. bond permanently untingthe4 tooth I4 with theplate. Si'ncejthe .strip I8a.. is .ernbedded at'the exactjplaceA Where the4 heat isl desir'edgfthe heat can .be exactly regulatedto cure or vulcanize the plastic material '20 Without burning or scorching. the plate. 4As 4shovvnin Figure?, .all'of the plate area. with the exception. of 'that immediately .surrounding the tooth I4 is uncovered and is unheated.

"The unit`22' includes acasing 24`ofmetal .or the like with an apertured end wall Ma, and an open bottom 24h. A. beror .otherv insulating. Washer 25 is inserted in thecasi'ng and bottomed against theend Wall 24a.. A heating element 26 has. a porcelain portion 21j Wi'th a shoulder Ela at the base ofi. the post v2`3` snugly seated in the Washer 215. VThis centers the post 2`3` in' the `aperture of. the `top VWall '2da thereby spacing. the. post from the casing 2E. The. element 2B has the porcelain portion 121 'thereof' surrounded by heat-insulating material such as` asbestos -'28.` 'This asbestos 28'-, in turn, is bottomedtby a cover-or Wall .29 and. an' electrical' conduit vfitting 3'0 forthe. element 26 depends :beneath the wall'. A 'wire .cord `3l' extendsfrom. the fitting .3U through the casing. to

'v a plug32 for supplying current to theelement.f A

um" tion, wallLZS. is. .preferably .completely filled with.

plasterazcement, or other ceramic .material 35, and.

tabsldcare turnedunderthersaid material 35.,tov hold it,.in;.the.casing. 24 as-shown Thesev tabs McA are.-.intearal withthepcasing- The unit I0 affords a good base for supporting the assembly as shown in Figure 7, and the lnsulation 28 eliminates the heating of the plate eX- cept through the fitting I8.

As best shown in Figure 8, the iitting I8 is conveniently formed from sheet or strip material, and the collar portion Ib thereof is split and easily formed from two ears on the strip.

In the event that two or more adjacent teeth are to be replaced in the plate, it may be desirable to provide a head or elo-ngated portion lc on the strip I8 as shown in Figure 9. This portion 18o will be embedded in the plaster il in the same manner described hereinabove but will bridge several tooth spaces to lie in closely spaced relation in front of several teeth. The head idc can be made as long as is necessary to bridge the tooth spaces.

From the above descriptions it will be understood that this invention provides a process of quickly replacing broken out or loosened teeth in dental plates without involving the investing of the complete plate in a mold and without ever subjecting the complete mold to a heat treatment. The process utilizes an insert iitting of heat-conducting material to supply heat to a thermosetting or bonding agent which is invested in a plaster of Paris mold that only surrounds the immediate vicinity of the tooth being replaced. The invention also includes the apparatus for eiecting the localized heating.

It will, of course, be understood that various details of construction may be varied through a Wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. The method of securing a tooth in xed position in the tooth space of a dental plate which comprises cutting a recess behind the tooth space in the plate, positioning a, tooth in the tooth space, pressing a dab of wax in the recess and against the lingual face of the tooth to temporarily hold the tooth in position in the plate, covering the buocal face of the tooth and the -adjoining buccal surface of the gingival portion of the plate with plastic plaster of Paris, inserting a heat-conducting tting into the plaster in closemolding the bonding material to build up the recessed portion into conformity with the lingual gingival plate portion, covering the molded bonding material with plaster of Paris, allowing the plaster of Paris to set, and heating the heatconducting tting for setting the bonding material.

2. The process of replacing a broken out tooth in a dental plate which comprises cutting a recess in the lingual gingival portion of the plate immediately adjacent the tooth space created by the broken out tooth, inserting a new tooth in the tooth space, investing the buccal sides of the new tooth and the adjoining gingival portion of the plate with plaster, embedding a heat-conductive strip into the plaster in closely spaced relation from the new tooth and plate, allowing the plaster to set to fixedly hold the new tooth on the plate, lling the recess with thermosetting plastic material, packing the thermosetting plastic material against the lingual face of the new tooth in firm anchoring relation therewith, investing the thermosetting plastic material in plaster, and heating the strip to thermoset the invested plastic material for integrally bonding the new tooth to the plate.

3. The method of replacing broken out teeth in dental plates without subjecting the plate to heating action sufiicient to cause discoloration which comprises inserting a new tooth in position on the plate, investing the buccal surfaces of the new tooth, the adjoining teeth, and the gingival portion of the plate in plaster, embedding a heat-conductive strip in the plaster, allowing the plaster to set, packing thermosetting material against the lingual face of the new tooth, molding the plastic material to the lingual gingival contour of the plate, investing the thermosetting material in plaster, and heating the strip to set the thermosetting plastic material for intely spaced relation to the tooth and plate, allow- 5 ing the plaster to set, melting out the wax, pressing thermosetting plastic bonding material into the recess against the lingual face of the tooth,

grally bonding the new tooth to the plate.

WALTER GIESE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 908,627 Telle Jan. 5, 1909 2,245,849 Ballard June 17, 1941 2,317,008 Werner Apr. 20, 1943 2,356,447 Cline Aug. 22, 1944 2,395,241 Allen Feb. 19, 1946 

